The grade scale

I've added this section to the course syllabus

Grade Scale: This class will be graded on a qualified curve, backed up by an absolute grade scale. This means that the higher of the two grades specified by tables below, where µ denotes the class average and ß denotes the class standard deviation:

Grade	Score		Grade	Class Rank
A+	97%+		A+	r >µ+1.3ß, historically the top 4.8%
A	93-96.99%		A	µ+1.3ß ≥ r > µ + 1.1ß, historically the top 10.2%
A-	90-92.99%		A-	µ+1.1ß ≥ r > µ + 0.95 ß, historically the top 16%
B+	87-89.99%		B+	µ+0.95 ß ≥ r > µ + 0.8 ß, historically the top 21%
B	83-86.99		B	µ+0.8 ß ≥ r > µ + 0.6ß, historically the top 29%
B-	80-82.99		B-	µ+0.6 ß ≥ r > µ + 0.45ß, historically the top 36%
C+	77-79.99		C+	µ+0.45 ß ≥ r > µ + 0.3 ß, historically the top 43%
C	70-76.99		C	µ+0.3 ß ≥ r > µ - 0.2 ß, historically the top 66%
D	60-69.99%		D	µ-0.2 ß ≥ r > µ - 0.55 ß, historically the top 77%
E	<60%		E	µ-0.55 ß ≥ r  historically bottom 23% (usually primarily people who did not complete the class)